S-91259A119 1/2"-13 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional Load-Bearing Capacity: With a tensile strength of 140,000 psi and minimum shear strength of 84,000 psi, this screw reliably handles high-stress applications without failure.
• Superior Corrosion Resistance: The black oxide finish provides a durable protective layer, extending service life in harsh industrial environments.
• Precision Shoulder for Accurate Alignment: The 5/8" diameter shoulder with tight tolerances ensures precise component positioning and reduces wear in assemblies.
• High-Strength Alloy Steel Construction: Made from alloy steel and hardened to Rockwell C32, it offers excellent durability and resistance to deformation under heavy loads.
• Secure and Easy Installation: The hex socket drive and knurled head allow for firm tool grip and efficient tightening, even in confined spaces.
• Reliable Thread Performance: Class 3A UNC coarse threads ensure a secure, vibration-resistant fit, ideal for dynamic or high-vibration settings.
• Compliance with Industry Standards: Meets ASME B18.3 specifications and is RoHS 3/REACH compliant, ensuring safety and regulatory adherence.

Professional Applications & Engineering Value

This alloy steel shoulder screw is engineered to address critical challenges in heavy-duty industrial applications, such as machinery assembly, automotive systems, and precision equipment. The 1/2"-13 UNC coarse thread with Class 3A fit provides superior holding power, reducing the risk of loosening under vibration and dynamic loads. The precisely machined 5/8" shoulder diameter with minimal tolerances ensures accurate alignment of components like bearings, gears, and pulleys, minimizing misalignment and wear. Combined with the black oxide finish, it offers enhanced corrosion resistance, making it suitable for environments exposed to moisture or chemicals. Its high tensile and shear strength ensures reliable performance in demanding scenarios, from conveyor systems to robotic arms, where failure is not an option.

Specification Summary & Compliance

This shoulder screw features a 1/2"-13 UNC thread with Class 3A fit for precise engagement, and a shoulder diameter of 5/8" with tolerances of -0.004" to -0.002". The shoulder length is 5/8" with a tolerance of -0.005" to 0.005", ensuring consistent performance. Manufactured to ASME B18.3 standards and compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, it meets rigorous quality and environmental requirements for industrial use.